Paclitaxel-induced neuropathy is an adverse event that often leads to therapeutic disruption and patient discomfort. We attempted to replicate a previously reported association between increased ...neuropathy risk and CYP2C8*3 genotype.
Demographic, treatment, and toxicity data were collected for paclitaxel-treated breast cancer patients who were genotyped for the CYP2C8*3 K399R (rs10509681) variant. A log-rank test was used in the primary analysis of European-American patients. An additional independent replication was then attempted in a cohort of African-American patients, followed by modeling of the entire patient cohort with relevant covariates.
In the primary analysis of 209 European patients, there was an increased risk of paclitaxel-induced neuropathy related to CYP2C8*3 status HR (per allele) = 1.93 (95% CI: 1.05–3.55), overall log-rank P = 0.006. The association was replicated in direction and magnitude of effect in 107 African-American patients (P = 0.043). In the Cox model using the entire mixed-race cohort (n = 411), each CYP2C8*3 allele approximately doubled the patient's risk of grade 2+ neuropathy (P = 0.004), and non-Europeans were at higher neuropathy risk than Europeans of similar genotype (P = 0.030).
The increased risk of paclitaxel-induced neuropathy in patients who carry the CYP2C8*3 variant was replicated in two racially distinct patient cohorts.
Tumor genome analysis is transforming cancer treatment by enabling identification of specific oncogenic drivers and selection of effective targeted agents. Meanwhile, patient genome analysis is being ...employed across therapeutic areas to inform selection of appropriate drugs and doses for treatment safety. Integration of patient genome analysis concurrent with preemptive tumor genetic testing will enable oncologists to make informed treatment decisions to select the right dose of the right drug for each patient and their tumor.
Purpose
A number of studies have tested the hypothesis that breast cancer patients with low-activity CYP2D6 genotypes achieve inferior benefit from tamoxifen treatment, putatively due to lack of ...metabolic activation to endoxifen. Studies have provided conflicting data, and meta-analyses suggest a small but significant increase in cancer recurrence, necessitating additional studies to allow for accurate effect assessment. We conducted a retrospective pharmacogenomic analysis of a prospectively collected community-based cohort of patients with estrogen receptor-positive breast cancer to test for associations between low-activity CYP2D6 genotype and disease outcome in 500 patients treated with adjuvant tamoxifen monotherapy and 500 who did not receive any systemic adjuvant therapy.
Methods
Tumor-derived DNA was genotyped for common, functionally consequential CYP2D6 polymorphisms (*2, *3, *4, *6, *10, *41, and copy number variants) and assigned a CYP2D6 activity score (AS) ranging from none (0) to full (2). Patients with poor metabolizer (AS = 0) phenotype were compared to patients with AS > 0 and in secondary analyses AS was analyzed quantitatively. Clinical outcome of interest was recurrence free survival (RFS) and analyses using long-rank test were adjusted for relevant clinical covariates (nodal status, tumor size, etc.).
Results
CYP2D6 AS was not associated with RFS in tamoxifen treated patients in univariate analyses (
p
> 0.2). In adjusted analyses, increasing AS was associated with inferior RFS (Hazard ratio 1.43, 95% confidence interval 1.00–2.04,
p
= 0.05). In patients that did not receive tamoxifen treatment, increasing CYP2D6 AS, and AS > 0, were associated with superior RFS (each
p
= 0.0015).
Conclusions
This population-based study does not support the hypothesis that patients with diminished CYP2D6 activity achieve inferior tamoxifen benefit. These contradictory findings suggest that the association between CYP2D6 genotype and tamoxifen treatment efficacy is null or near null, and unlikely to be useful in clinical practice.
Identification of fetal kidney anomalies invites questions about underlying causes and recurrence risk in future pregnancies. We therefore investigated the diagnostic yield of next‐generation ...sequencing in fetuses with bilateral kidney anomalies and the correlation between disrupted genes and fetal phenotypes. Fetuses with bilateral kidney anomalies were screened using an in‐house‐designed kidney‐gene panel. In families where candidate variants were not identified, whole‐exome sequencing was performed. Genes uncovered by this analysis were added to our kidney panel. We identified likely deleterious variants in 11 of 56 (20%) families. The kidney‐gene analysis revealed likely deleterious variants in known kidney developmental genes in 6 fetuses and TMEM67 variants in 2 unrelated fetuses. Kidney histology was similar in the latter 2 fetuses—presenting a distinct prenatal form of nephronophthisis. Exome sequencing identified ROBO1 variants in one family and a GREB1L variant in another family. GREB1L and ROBO1 were added to our kidney‐gene panel and additional variants were identified. Next‐generation sequencing substantially contributes to identifying causes of fetal kidney anomalies. Genetic causes may be supported by histological examination of the kidneys. This is the first time that SLIT‐ROBO signaling is implicated in human bilateral kidney agenesis.
Oral semaglutide is the first oral formulation of a glucagon-like peptide-1 (GLP-1) receptor agonist developed for the treatment of type 2 diabetes. We aimed to compare the efficacy and safety of ...flexible dose adjustments of oral semaglutide with sitagliptin 100 mg.
In this 52-week, multicentre, randomised, open-label, phase 3a trial, we recruited patients with type 2 diabetes from 81 sites in ten countries. Patients were eligible if they were aged 18 years or older (19 years or older in South Korea), had type 2 diabetes (diagnosed ≥90 days before screening), HbA
of 7·5-9·5% (58-80 mmol/mol), and were inadequately controlled on stable daily doses of one or two oral glucose-lowering drugs (for 90 days or more before screening). Participants were randomly assigned (1:1) by use of an interactive web-response system, stratified by background glucose-lowering medication at screening, to oral semaglutide with flexible dose adjustments to 3, 7, or 14 mg once daily or sitagliptin 100 mg once daily. To approximate treatment individualisation in clinical practice, oral semaglutide dose could be adjusted on the basis of prespecified HbA
and tolerability criteria. Two efficacy-related estimands were prespecified: treatment policy (regardless of treatment discontinuation or use of rescue medication) and trial product (on treatment and without use of rescue medication) for participants randomly assigned to treatment. The primary endpoint was achievement of HbA
of less than 7% (53 mmol/mol) at week 52 and the confirmatory secondary efficacy endpoint was change in bodyweight from baseline to week 52. Safety was assessed in all participants who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, number NCT02849080, and European Clinical Trials Database, EudraCT number 2015-005593-38, and an open-label extension is ongoing.
Between Sept 20, 2016, and Feb 7, 2017, of 804 patients assessed for eligibility, 504 were eligible and randomly assigned to oral semaglutide (n=253) or sitagliptin (n=251). Most participants were male (285 57% of 504) with a mean age of 57·4 years (SD 9·9). All participants were given at least one dose of their allocated study drug except for one participant in the sitagliptin group. From a mean baseline HbA
of 8·3% (SD 0·6%; 67 mmol/mol SD 6·4), a greater proportion of participants achieved an HbA
of less than 7% with oral semaglutide than did with sitagliptin (treatment policy estimand: 58% 134 of 230 vs 25% 60 of 238; and trial product estimand: 63% 123 of 196 vs 28% 52 of 184). The odds of achieving an HbA
of less than 7% was significantly better with oral semaglutide than sitagliptin (treatment policy estimand: odds ratio OR 4·40, 95% CI 2·89-6·70, p<0·0001; and trial product estimand: 5·54, 3·54-8·68, p<0·0001). The odds of decreasing mean bodyweight from baseline to week 52 were higher with oral semaglutide than with sitagliptin (estimated mean change in bodyweight, treatment policy estimand: -2·6 kg SE 0·3 vs -0·7 kg SE 0·2, estimated treatment difference ETD -1·9 kg, 95% CI -2·6 to -1·2; p<0·0001; and trial product estimand: -2·9 kg SE 0·3 vs -0·8 kg SE 0·3, ETD -2·2 kg, -2·9 to -1·5; p<0·0001). Adverse events occurred in 197 (78%) of 253 participants in the oral semaglutide group versus 172 (69%) of 250 in the sitagliptin group, and nausea was the most common adverse event with oral semaglutide (53 21%). Two deaths occurred in the sitagliptin group during the trial.
Oral semaglutide, with flexible dose adjustment, based on efficacy and tolerability, provided superior glycaemic control and weight loss compared with sitagliptin, and with a safety profile consistent with subcutaneous GLP-1 receptor agonists.
Novo Nordisk A/S.
Drug-drug interactions (DDIs) in subjects enrolling in clinical trials can impact not only safety of the patient but also study drug outcomes and data validity. This makes it critical to adequately ...screen and manage DDIs. The study objective was to determine the prevalence of DDIs involving study medications in subjects enrolling in National Clinical Trials Network (NCTN) clinical trials at a single institution. DDIs were evaluated based on study protocol recommendations for concomitant medication use (i.e. exclude, avoid or use caution), screening via DDI tool, and pharmacist review.
Subjects enrolled in NCTN trials of commercially available agents between January 2013 and August 2017 were included if a complete medication list was available. Complete medication lists were collected from the date of enrollment or the next available date then screened utilizing protocol guidance and the DDI screening tool, Lexicomp® Drug Interactions (Wolters Kluwer, Hudson, OH). Interactions were reviewed for clinical relevance: defined as a DDI that would require a medication change to ensure study agent safety and efficacy at enrollment.
One hundred and twenty-eight subjects enrolled in 35 clinical trials were included. Protocol guidance detected 15 unique DDI pairs that should be avoided or used with caution in 10.2% (13/128) of subjects. The majority of these subjects did not have a clinically relevant DDI (69.2%, 9/13) based on pharmacist review. Lexicomp® detected moderate to major DDIs in 24.2% (31/128) of subjects, with 9.4% (12/128) having a clinically relevant DDI.
This study confirms a high prevalence of DDIs present in subjects enrolling in oncology clinical trials. Further efforts should be made to improve methods to detect and manage DDIs in patients enrolling on clinical trials to ensure patient safety and trial data validity.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Discovery of clinical and genetic predictors of exemestane pharmacokinetics was attempted in 246 postmenopausal patients with breast cancer enrolled on a prospective clinical study. A sample was ...collected 2 h after exemestane dosing at a 1- or 3-month study visit to measure drug concentration. The primary hypothesis was that patients carrying the low-activity CYP3A4*22 (rs35599367) single-nucleotide polymorphism (SNP) would have greater exemestane concentration. Additional SNPs in genes relevant to exemestane metabolism (CYP1A1/2, CYP1B1, CYP3A4, CYP4A11, AKR1C3/4, AKR7A2) were screened in secondary analyses and adjusted for clinical covariates. CYP3A4*22 was associated with a 54% greater exemestane concentration (P<0.01). Concentration was greater in patients who reported White race, had elevated aminotransferases, renal insufficiency, lower body mass index and had not received chemotherapy (all P<0.05), and CYP3A4*22 maintained significance after adjustment for covariates (P<0.01). These genetic and clinical predictors of exemestane concentration may be useful for treatment individualization in patients with breast cancer.
Using data collected with the CLEO detector operating at the CESR e+e- collider at sqrts=3.97-4.26 GeV, we investigate 15 charmonium decay modes of the psi(4040), psi(4160), and Y(4260) resonances. ...We confirm, at 11 sigma significance, the BABAR Y(4260)-->pi+pi- J/psi discovery, make the first observation of Y(4260)--> pi(0)pi(0) J/psi (5.1 sigma), and find the first evidence for Y(4260)-->K+K- J/psi(3.7 sigma). We measure e+e- cross sections at sqrts=4.26 GeV as sigma(pi+pi- J/psi)=58(+12)(-10)+/-4 pb, sigma(pi(0)pi(0) J/psi)=23(+12)(-8)+/-1 pb, and sigma(K+K- J/psi)=9(+9)(-5)+/-1 pb, in which the uncertainties are statistical and systematic, respectively. Upper limits are placed on other decay rates from all three resonances.
Breast cancer is the most frequent cause of cancer death in low- and middle-income countries, in particular among sub-Saharan African women, where response to available anticancer treatment therapy ...is often limited by the recurrent breast tumours and metastasis, ultimately resulting in decreased overall survival rate. This can also be attributed to African genomes that contain more variation than those from other parts of the world. The purpose of this review is to summarize published evidence on pharmacogenetic and pharmacokinetic aspects related to specific available treatments and the known genetic variabilities associated with metabolism and/or transport of breast cancer drugs, and treatment outcomes when possible. The emphasis is on the African genetic variation and focuses on the genes with the highest strength of evidence, with a close look on CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP3A4/5, CYP19A1, UGT1A4, UGT2B7, UGT2B15, SLC22A16, SLC38A7, FcgammaR, DPYD, ABCB1, and SULT1A1, which are the genes known to play major roles in the metabolism and/or elimination of the respective anti-breast cancer drugs given to the patients. The genetic variability of their metabolism could be associated with different metabolic phenotypes that may cause reduced patients' adherence because of toxicity or sub-therapeutic doses. Finally, this knowledge enhances possible personalized treatment approaches, with the possibility of improving survival outcomes in patients with breast cancer. Keywords: breast cancer, genetic variability, inter-ethnic differences, pharmacogenetics, sub-Saharan Africa, toxicity
Field ion source development for neutron generators Bargsten Johnson, B.; Schwoebel, P.R.; Holland, C.E. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
01/2012, Letnik:
663, Številka:
1
Journal Article
Recenzirano
Odprti dostop
An ion source based on the principles of electrostatic field desorption is being developed to improve the performance of existing compact neutron generators. The ion source is an array of gated metal ...tips derived from field electron emitter array microfabrication technology. A comprehensive summary of development and experimental activities is presented. Many structural modifications to the arrays have been incorporated to achieve higher tip operating fields, while lowering fields at the gate electrode to prevent gate field electron emission which initiates electrical breakdown in the array. The latest focus of fabrication activities has been on rounding the gate electrode edge and surrounding the gate electrode with dielectric material. Array testing results have indicated a steady progression of increased array tip operating fields with each new design tested. The latest arrays have consistently achieved fields beyond those required for the onset of deuterium desorption (∼20
V/nm), and have demonstrated the desorption of deuterium at fields up to 36
V/nm. The number of ions desorbed from an array has been quantified, and field desorption of metal tip substrate material from array tips has been observed for the first time. Gas-phase field ionization studies with ∼10,000 tip arrays have achieved deuterium ion currents of ∼50
nA. Neutron production by field ionization has yielded ∼10
2
n/s from ∼1
mm
2 of array area using the deuterium–deuterium fusion reaction at 90
kV.
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